[quote user="SteveYates"] When delivering mail to a mailing list, Mercury resolves the MXs first and then tries to deliver messages destined for the same MX together in one SMTP session instead of separately.

 <snip>

T 20070509 092400 4641d236 Established ESMTP connection to 64.18.7.10
T 20070509 092400 4641d236 MAIL FROM:<Mary@example.org>
T 20070509 092400 4641d236 250 Ok
T 20070509 092400 4641d236 RCPT TO:<user@example.com>
T 20070509 092401 4641d236 250 Ok
T 20070509 092401 4641d236 RCPT TO:<user2@example.net>
W 20070509 092401 4641d236 451 Recipients not all at same mail host - psmtp[/quote]

Why doesn't postini allow this? And as a consequence why have the mailadmin set the same mx for both domains, if postini doesn't allow this behaviour?

Have you asked the postmaster at 64.18.7.10 about this issue?

When delivering mail to a mailing list, Mercury resolves the MXs first and then tries to deliver messages destined for the same MX together in one SMTP session instead of separately.  Unfortunately Postini does not allow that, because after the first RCPT TO's domain name, (I suspect) Postini goes into the mode of using "that domain's settings" and rejects other messages, originally with a temp error.  A sample log for this is below.  Note user2@example.net below is not a member of the example.com account settings, so gets a 451 error.

T 20070509 092400 4641d236 Established ESMTP connection to 64.18.7.10
T 20070509 092400 4641d236 MAIL FROM:<Mary@example.org>
T 20070509 092400 4641d236 250 Ok
T 20070509 092400 4641d236 RCPT TO:<user@example.com>
T 20070509 092401 4641d236 250 Ok
T 20070509 092401 4641d236 RCPT TO:<user2@example.net>
W 20070509 092401 4641d236 451 Recipients not all at same mail host - psmtp
T 20070509 092401 4641d236 RCPT TO:<user3@other.example.net>

W 20070509 092401 4641d236 451 Recipients not all at same mail host - psmtp

When this happens, Mercury will start retrying the list of pending messages, every 30 (or whatever) minutes delivering one more name off the top of the list each time.

Is it possible to configure Mercury to NOT try to deliver mail for multiple domains, that is destined for the same MX, together?  Delivering to multiple users on the same domain is OK but mixing domains seems to cause the problem.

 - Steve Yates
 - ITS, Inc.
 - If a little knowledge is dangerous, why spend time studying?

~ Taglines by Taglinator - www.srtware.com ~

[quote user="SteveYates"]When this happens, Mercury will start retrying the list of pending messages, every 30 (or whatever) minutes delivering one more name off the top of the list each time.[/quote]

The effect of this can actually be a serious problem.  For 10 domains it's not an issue, it will eventually retry enough times to get through the list.  If there are 1000 domains on a large mailing list however the message will likely hit the retry limit and expire the message before processing all the addresses.

 - Steve Yates
 - ITS, Inc.
 - If you shoot a mime, should you use a silencer?

~ Taglines by Taglinator - www.srtware.com ~